Electricity has been used to treat pain for over 100 years. Electrical stimulation may directly block transmission of pain signals along nerves and has been shown to promote the release of endorphins, which are natural painkillers produced by the body. Electrical stimulation modalities of the background art include, but are not limited to: Transcutaneous Electrical Nerve Stimulation (TENS), Interferential Current (IFC) and Galvanic Stimulation (GC).
Transcutaneous electrical nerve stimulation (TENS) is a simple, non-invasive analgesic technique that is used extensively in health-care settings by physiotherapists, nurses and midwifes (Johnson, 1997; Pope, Mockett and Wright, 1995; Reeve, Menon and Corabian, 1996; Robertson and Spurritt, 1998). TENS is commonly used in the treatment of a variety of conditions, including, among others: Arthritis, Phantom limb pain following amputation, Lumbago, Post operative pain, Sports injury, Amputation, Skeletal pains, Whiplash, Rheumatoid and osteo-arthritis, menstrual (Period) pain, Pain associated with chronic fatigue syndrome, Neuralgia, Back pain, Most muscle pains and Cancer pain. Further information, defining the different aspects of TENS is provided in Mark Johnson, Transcutaneous Electrical stimulation (TENS), Chapter 17, which is incorporated herein in its entirety for background information.
Interferential current (IFC) is essentially a deeper form of TENS. In essence, IFC modulates a high frequency (4000 Hz) carrier waveform with the same signal produced by a TENS unit. The high frequency carrier waveform penetrates the skin more deeply than a regular TENS unit, with less user discomfort for a given level of stimulation. Deep in the tissues, the carrier waveform is cancelled out, resulting in a TENS-like signal deep under the skin.
Galvanic stimulation (GS) is useful in acute injuries associated with major tissue trauma, bleeding or swelling. In contrast to TENS and IFC units, which apply alternating current, galvanic stimulators apply direct current. Direct current creates an electrical field over the treated area that theoretically, changes blood flow. Galvanic stimulation can be delivered in a continuous direct current mode or in a pulse mode.
Iontophoresis is an effective and painless method of delivering cosmetic and pharmaceutical active agents to a localized tissue area by applying electrical current to a formulation of the medication. The two principal mechanisms by which electrical currents enhance molecular transport across the skin are: (a) Iontophoresis, in which a charged ion is repelled from an electrode of the same charge, and (b)Electroosmosis, the convective movement of solvent that occurs through a charged “pore” in response to the preferential passage of counter-ions when the electric field is applied.
The stimulating devices of the background art, which use TENS, IFC and GC stimulation are limited in the degree of relief these devices can provide.
There is therefore a need for an apparatus and method, such as is disclosed in the present invention, to provide an improved stimulating apparatus, for better, more effective treatment.